kernelconfig_penguin
default or selected kernelversion does not have config value CONFIG_AIC79XX_ENABLE_RD_STRM.
Result is shown for kernelversion 2.6.21.7

Enable Read Streaming for All Targets

configname: CONFIG_AIC79XX_ENABLE_RD_STRM

Linux Kernel Configuration
└─> Enable Read Streaming for All Targets

Read Streaming is a U320 protocol option that should enhance
performance. Early U320 drive firmware actually performs slower
with read streaming enabled so it is disabled by default. Read
Streaming can be configured in much the same way as tagged queueing
using the "rd_strm" command line option. See
drivers/scsi/aic7xxx/README.aic79xx for details.